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Notes on Using PK Protect Attachments

  • The PK Protect and PK Protect Options buttons may not appear if you use Send To Mail Recipient to send attachments from Word or other common desktop applications. With Outlook, if the buttons are not available, you can use the tool tray icon and/or menu to turn compression on/off or to modify options.

  • Recipients of email attachments compressed with the Deflate64(tm)algorithm must use SecureZIP or version 2.50 or later of PKZIP to extract the files.

  • Recipients of attachments compressed with strong encryption must use version 6.0 or later of PKZIP or SecureZIP to extract the files.

  • Recipients of attachments encrypted in PKZIP7.0 (or a later version of PKZIP or SecureZIP) using strong, X.509-certificate-based encryption need version 6.1 or later of PKZIP or SecureZIP to decrypt. Files encrypted using strong passphrase-based encryption can be decrypted by version 6.0 or later of PKZIP or SecureZIP.

  • If you send or forward an encrypted ZIP archive with the Re-Encrypt option selected, you can use an alternate ZIP extension for the attachment. The ZIP archive will be re-encrypted with the alternate extension.

  • You need a digital certificate if you want to use certificate-based encryption or add digital signatures to email attachments.

Still Need Help?

For assistance using PK Protect Attachments or to report a problem, visit our Web site at:

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